Low-profile separators will be installed between the seats rather than armrests, which are uncomfortable for large people, restrict movement between the aisle and window seats, and eliminate extra seating space for small children. Armrests may remain on seats near doors, where passengers could slide off when trains speed up and slow down.

Seat upholstery will be easy to clean and be constructed with medium-density foam cushions and a contoured seat back with lumbar support.

More room is available under the seats for carry-on bags.

Floor-to-ceiling poles will give passengers something to hold while cars start and stop. But they will be spaced to provide adequate room for wheelchairs.

For the most part, the nine-member elected BART board liked what it saw.

But the bike rack remains a contentious amenity.

The new design includes one, although the agency has abandoned the idea of installing adjacent flip-down seats that could be used when no bicycles are on board. It could generate unwanted conflict, Weinstein said.

BART cars are already crowded; the new cars will have five fewer seats than the old ones, and the racks take up the equivalent of three additional seats, said BART directors Gail Murray of Walnut Creek and Zackhary Mallet of El Sobrante.

"My constituents have told me they want a seat," Murray said. "We should look at something other than these racks that take up so much space."

Bike proponents on the board argue that BART already allows bikes on trains, and the racks are safer than propping them up along the aisles or against the walls.

And since many of BART's parking lots routinely fill up, the rail service needs to encourage cyclists, BART Director Rebecca Saltzman of Oakland said.

The BART board and the riding public will have an opportunity to see a full-size railcar prototype in April. BART plans to purchase 1,000 railcars through 2023.